We give a generalization of Hochster’s formula for local cohomologies of square-free monomial ideals to monomial ideals, which are not necessarily square-free. Using this formula, we give combinatorial characterizations of generalized Cohen-Macaulay monomial ideals. We also give other applications of the generalized Hochster’s formula.

A monomial Hénon mapping is defined as the wellknown two-dimensional Hénon map with the quadratic term replaced by a monomial. This paper introduces a conjecture about monomial Hénon mappings: Even Hénon mappings are chaotic and odd Hénon mappings are not chaotic in the first quadrant of the bifurcation parameter space. This conjecture is based on numerical simulations of this type of map.

In this paper we describe an algorithm for producing infinitely many examples of set-theoretic complete intersection monomial curves in P n+1 , starting with a single set-theoretic complete intersection monomial curve in P n. Moreover we investigate the numerical criteria to decide when these monomial curves can or cannot be obtained via semigroup gluing.

Proofs of two results about a monomial ideal – describing membership in auxiliary ideals associated to the monomial ideal – are given which do not invoke resolution of singularities. The AM–GM inequality is used as a substitute for taking a log resolution of the monomial ideal.

d-Monomial tests are statistical randomness tests based on Algebraic Normal Form representation of a Boolean function, and were first introduced by Filiol in 2002. We show that there are strong indications that the Gate Complexity of a Boolean function is related to a bias detectable in a d-Monomial test. We then discuss how to effectively apply d-Monomial tests in chosen-IV attacks against str...

A k-automorphism σ of the rational function field k(x1, . . . , xn) is called purely monomial if σ sends every variable xi to a monic Laurent monomial in the variables x1, . . . , xn. Let G be a finite subgroup of purely monomial k-automorphisms of k(x1, . . . , xn). The rationality problem of the G-action is the problem of whether the G-fixed field k(x1, . . . , xn) G is k-rational, i.e., pure...

We describe an algorithm for explicitly listing the irreducible monomial subgroups of GL(n, q) , given a suitable list of finite irreducible monomial subgroups of GL(n, C) , where n is 4 or a prime, and q is a prime power. Particular attention is paid to the case n = 4, and the algorithm is illustrated for n = 4 and q = 5. Certain primitive permutation groups can be constructed from a list of i...

One studies Cremona monomial maps by combinatorial means. Among the results is a simple integer matrix theoretic proof that the inverse of a Cremona monomial map is also defined by monomials of fixed degree, and moreover, the set of monomials defining the inverse can be obtained explicitly in terms of the initial data. A neat consequence is drawn for the plane Cremona monomial group, in particu...

We develop the theory of truncated wedge schemes, a higher dimensional analog of jet schemes. We prove some basic properties and give an irreducibility criterion for truncated wedge schemes of a locally complete intersection variety analogous to Mustaţǎ’s for jet schemes. We show that the reduced subscheme structure of a truncated wedge scheme of any monomial scheme is itself a monomial scheme ...